Hi,
I have a question regarding Relay X1. Normally I can switch the relay on or off with my FEZ Spider and then a circuit will be closed. But I need something which informs my board by itself if the circuit is closed, e.g. when someone rings a doorbell. And now my questions:
Can I use the relay both ways so that’ll inform my board if some other source has switched it on or off? If not is there a way I can do this?
Thanks in advance for your help,
Mike
Welcome to the forum
You probably want to learn some stuff about GPIO. Maybe check here for conceptual stuff: http://www.bit-101.com/blog/?p=3813
And after that check: https://www.ghielectronics.com/docs/5/digital-inputs
If its your first play with hardware it might be difficult, but you are welcome to ask more.
@ njbuch - Thank you very much for your answer. 
So if I understand it correct, I can connect any “outside”-circuit to my board (as long as I use enough resistors) and when the circuit ist closed, for example someone press the button of the doorbell I’ll get a InterruptEvent. Correct so far?
Indeed.
(You probably just experienced “the digital enlightening” 
)
@ andre.m - I’m mean the “outside” may have higher current than my board can handle so I need one or more resistors to reduce the current.
Forgive me, if I mix up some words but english is not my native language neither is electricity